Uptake And Utilization Of Nitrogen By Crops

After nitrogen-deficient plants are applied with appropriate amount of nitrogen fertilizer, a large amount of high molecular nitrogen-containing organic matter is synthesized in the body, which makes the plant grow rapidly and the leaf color becomes black. Therefore, in the production practice, the effect of nitrogen fertilizer is most likely to change from the appearance and leaf color of the plant. observed.

Although ammonium nitrogen and nitrate nitrogen have the same value as plant nitrogen sources, there are still significant differences in the relative uptake of different plants under the conditions where the two nitrogen sources can be selected. This difference is affected by factors such as the type, variety and growth period of the plant, the reaction of the soil solution (PH), the relative content of various ions in the solution, and the concentration of the two nitrogen sources. Among field crops, dry crops such as tobacco and cotton have a better response to nitrate nitrogen, while rice absorbs more ammonium nitrogen.

Plants can directly absorb urea and certain ammonium salts as nitrogen sources through leaves and roots. However, the assimilation process of urea in the body has not been fully understood. It is generally believed that urea is decomposed into ammonium nitrogen under the action of urease in the crop body and then used.